Navigation Links
Genital Herpes May Never Go Dormant
Date:11/18/2009

Study finds low level shedding may be continuous, infection state unclear

WEDNESDAY, Nov. 18 (HealthDay News) -- Herpes, the sexually transmitted disease that causes genital lesions, never truly goes into a dormant state, new research suggests.

As a matter of fact, even when it's not causing an outbreak, the virus is shedding tiny bits of itself in the genital tract.

While the study did not specifically address whether or not the very small amounts of virus being continually shed are enough to infect someone else, the findings have the potential to change the way in which scientists view the life cycle of the disease.

The herpes virus is believed to hide out in the neurons around the spine during latent periods, then periodically travel down neurons that end in the genital tract, where it infects the skin cells, causing a lesion.

The accepted view is that the virus was largely inactive during latent periods, said study author Dr. Joshua Schiffer, a senior fellow at the University of Washington in Seattle.

"We've known for many years that herpes maintains a latent state in the nerves around the spinal cord. In effect, it hibernates there," Schiffer said. "The older idea was that it didn't do much while it was there ... But what our model suggests is the virus is continually being released from the neurons."

The study appears in the Nov. 18 issue of Science Translational Medicine.

The study looked at herpes simplex 2 virus, not herpes simplex 1 virus, which causes cold sores or fever blisters, though it can also cause genital lesions. Schiffer said he suspected the findings would hold true for herpes simplex 1 as well, though previous studies suggest herpes simplex 1 may shed less often.

Schiffer and his colleagues used data from two previous studies. In the first, participants swabbed their genitals every day during an outbreak and until their lesions went away. In the second, patients swabbed their genitals four times a day for 60 days, even when they were asymptomatic.

The data was then put into a mathematical model to determine the probable rate of shedding. According to the study, 85 percent of shedding episodes were asymptomatic, or did not cause a lesion. About 60 percent lasted less than 12 hours.

About 45 million Americans, or one in five over the age of 12, are infected with the genital herpes virus in the United States, according to the U.S. Centers for Disease Control and Prevention. But many of them aren't aware they are infected because they've never had, or have never been aware of, their lesions. "Within their skin there is this constant battle going on within the virus and the immune system," Schiffer explained.

Typically, patients are counseled to avoid having sex during an outbreak and to use a condom to prevent transmission when they are not having symptoms.

Antiviral drugs available, including acyclovir, valacyclovir and famciclovir, can control many, but not all, outbreaks, Schiffer said.

Nancy Sawtell, a researcher in the division of infectious diseases at Cincinnati Children's Hospital Medical Center, said the study opens up new avenues for research. But it's too soon to suggest that low levels of viral DNA necessarily mean a person can still infect another.

She noted that the researchers tested for viral DNA, which is only a portion of the virus and doesn't in and of itself mean a person is infectious. "The presence of viral DNA does mean you are infected, but it doesn't necessarily mean you have an infectious particle there," Sawtell said.

Secondly, because the neurons themselves were not examined, it's possible the viral DNA that's present could have originated from somewhere else in the body. Previous animal studies have shown herpes does indeed go into an inactive state.

"It would be really nice to be able to look at the neurons in this human model to determine that the virus is coming from the spine, and wasn't just present in the genitalia and missed by an earlier swab," Sawtell said.

Couples trying to avoid infecting one partner should continue to take the same precautions they did prior to the study, including using condoms even when asymptomatic.

"I wouldn't panic over it," Sawtell said. "We have a lot to learn about how infectious these low levels of viral DNA actually are."

More information

There's more on herpes at the U.S. Centers for Disease Control and Prevention.



SOURCES: Joshua Schiffer, M.D., research associate, Fred Hutchinson Cancer Research Center, and senior fellow, University of Washington, Seattle; Nancy Sawtell, Ph.D., researcher, division of infectious diseases, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio; Nov. 18, 2009, Science Translational Medicine


'/>"/>
Copyright©2009 ScoutNews,LLC.
All rights reserved

Related medicine news :

1. Pitt part of $100 million NHLBI Bench to Bassinet effort in congenital heart disease
2. 1 shot of gene therapy and children with congenital blindness can now see
3. Fewer Genital Warts Thanks to HPV Vaccine Program
4. Orgasms, sexual health and attitudes about female genitals
5. Scientists learn why even treated genital herpes sores boost the risk of HIV infection
6. Oral and Maxillofacial Surgeons Applaud Senator Mary Landrieu (D-LA) For Introducing Legislation to Require Insurance Coverage for Children With Congenital Deformities
7. Researchers identify the gene responsible for a rare form of congenital anemia
8. Large congenital and solitary intrahepatic arterioportal
9. For the First Time in U.S. History, Congress Addresses the Needs of the Congenital Heart Defect Population by Introducing the Congenital Heart Futures Act
10. Oral and Maxillofacial Surgeons Applaud Congresswoman McCarthys Legislation to Require Insurance Coverage for Children With Congenital Deformities
11. Female genital mutilation among Israels Negev Bedouins has virtually disappeared -- BGU study
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:9/25/2017)... (PRWEB) , ... September 25, 2017 , ... The Asset ... solution. It is as simple as scanning the bar code of the product ... sent to a secure internet cloud where violations are automatically generated and exception alerts ...
(Date:9/25/2017)... ... September 25, 2017 , ... ... is not an option to senior, upper-level executives speaking at a business luncheon ... "A senior, high-level executive is an asset to be fully realized and activated ...
(Date:9/25/2017)... ... September 25, 2017 , ... Earlypicker is expanding its offerings ... shop for the hottest Korean cosmetics and fashion trends sweeping the nation. The decision ... already well-known for the great offerings that allow Koreans everywhere to look their best ...
(Date:9/25/2017)... ... ... “Renew Refresh Restore Reward”: is a story of struggle and how trouble often ... Deborah Freeman, cofounded the Free Spirit Bible Church and currently serves as the church’s ... invited us to come over before the baby had to go back to her ...
(Date:9/25/2017)... ... September 25, 2017 , ... “Grandpa's Visit”: a tender and relatable ... with the others. “Grandpa's Visit” is the creation of published author, Beverly Brumfield, gifted ... much like the character in her book. She shares, “Mr. Rice is struggling to ...
Breaking Medicine News(10 mins):
(Date:9/22/2017)... 2017  As the latest Obamacare repeal effort moves ... (R-LA) and Lindsey Graham (R-SC) medical ... device industry is in an odd place.  The industry ... excise tax on medical device sales passed along with ... patients, increased visits and hospital customers with the funding ...
(Date:9/18/2017)... , Sept. 18, 2017  PMD Healthcare of ... Pharmacy of Kalamazoo, Mich. , have ... service that expedites and streamlines patient and provider access ... 2.0, and wellness management services.  ... used to measure lung function for a variety of ...
(Date:9/12/2017)... -- Consumer reviews on the independent review site Consumer Affairs ... for hearing aids, ranking it higher than Miracle Ear ™, ... ... Hearing Aids ... store that provides high performance, state-of-the-art, German-engineered hearing aids directly to ...
Breaking Medicine Technology: